Shvetsov M-11F

The Shvetsov M-11 was designed under a 1923 competition in the Soviet Union for a new engine to power trainer aircraft. It is a single-row five-cylinder air-cooled radial piston engine with aluminum cylinder heads. Uniquely, pushrods actuating the valves were driven by individual cams on each cylinder rather than a single central cam. The initial versions of the M-11 suffered from a short service life of only 50 hours. Basic M-11 engine had power output 100 hp (73 kW), newer variant M-11D - 125 hp (92 kW). The ultimate version, M-11FR, introduced in 1946, increased output to 160 hp at 1,900 rpm on takeoff and 140 hp at cruise and had provisions for a variable-pitch propeller, accessory drive (for vacuum pumps, compressors, generators, etc.) and featured a floatless carburetor.

M-11 powered a number of aircraft, including Polikarpov Po-2, Yakovlev UT-1, Yakovlev UT-2, Yakovlev Yak-6, Yakovlev Yak-12, Yakovlev Yak-18 and Mikoyan-Gurevich MiG-8. It also powered the Polish LWD Junak and PZL S-4 Kania. M-11 remained in production until 1952 with an estimated total of over 100,000 engines made. Several hundreds were manufactured under license in Polish WSK-Kalisz works in Kalisz (M-11D and M-11FR-1).

[edit] Specifications (M-11)

General characteristics

• Type: 5-cylinder air-cooled radial engine
• Bore: 125mm (4.92 in)
• Stroke: 140mm (5.51 in)
• Displacement: 8.6 L (525 in³)
• Dry weight: 165 kg (363 lb)

Components

• Cooling system: Air-cooled

Performance

• Power output:
  
  • 82 kW (110 hp) at 1,650 rpm for takeoff
  • 75 kW (100 hp) cruise
• Specific power: 9.5 kW/L (0.21 hp/in³)
• Compression ratio: 5.0:1
• Power-to-weight ratio: 0.50 kW/kg (0.30 hp/lb)